| A | B |
|---|
| adenine | a purine base; a component of nucleotide |
| bateriophage | virus that infects bacteria |
| base-pairing rules | Chargraff's rules |
| complementary | characteristic of nucleotide |
| cytosine | nitrogeneous base |
| deoxyribose | five-carbon sugar |
| DNA polymerase | enzyme that catalyzes the replication of DNA |
| double helix | spiral staircase structure characteristic of DNA molecule |
| exon | sequence of nucleotides that gets translated and transcribed |
| helicase | enzyme that unwinds a DNA molecule 's double helix before replication |
| intron | segment of mRNA transcribed from eukaryotic DNA but removed before translation of mRNA into a protein. |
| guanine | nitrogen base of the purine class; component of DNA and RNA nucleotides. |
| multigene family | group of genes that has evolved from a single ancestral gene and is characterized by the ezxistence of multiple copies. |
| nucleotide | subunit of nucleic acids consisting of a nitrogenous base, a sugar, and a phosphate group. |
| purine | class of organic, nitrogenous molecules in nucleic acids that have a double ring of carbon and nitrogen. |
| pyrimidine | class of organic, nitrogenous molecules in nucleic acids that have a single ring of carbon and nitrogen. |
| replication | precess of synthesizing a new strand of DNA. |
| replication fork | point at which the double helix of DNA separates so that it can be copied. |
| thymine | nitrogenous base of the pyrimidine class; component of DNA. |
| transformation | the transfer of genetic material from one organism to another; first observed by Griffith |
| transposon | gene that has the ability to move from one chromosomal location to another |
| vaccine | substance prepared from killed or weakened pathogens and introduced into a body to produce immunity |
| virulent | referring to the deadliness of a disease-causing agent |
